While it is apparent that catheters for post-surgical drainage and other medical purposes should be securely positioned so that they are not inadvertently dislodged or withdrawn by patient movement or by bedside activities of physicians and hospital staff, and while it is apparent that the wound or incision area, including the skin surrounding the point of entry, should be protected against the irritating and excoriating effects of fluid contact, prior devices have generally fallen far short of achieving such objectives, at least without introducing additional problems that offset the improvements. For example, to help immobilize an indwelling catheter, it is a common practice to suture the catheter to a retention device and also suture the retention device to a patient's skin. The former does not always insure against catheter movement, and the latter may result in irritation, infection, and considerable patient discomfort over the typical period of catheter placement (usually 5 to 7 days). Thus, in published UK application No. 2,147,811A, sutures are shown for the purpose of securing the device to the patient's skin, although the use of adhesives is also mentioned. In U.S. Pat. No. 4,392,854, adhesive tape may be used to hold the device in place but sutures are indicated for connecting the catheter to the supporting device.
Other catheter retention devices are disclosed in U.S. Pat. Nos. 4,360,025, 4,261,363, 3,138,158, 3,682,180, and 4,490,141. The use of adhesives is frequently disclosed for attaching a retention device to a patient's skin, but in some cases the retaining devices block medical inspection of the wound or incision, and in other cases the catheters are not supported at generally right angles (normal to) the surface of the skin. In still other instances, attachment of the supporting devices is relatively awkward and inconvenient, increasing the possibilities of patient discomfort. Thus, a construction that requires a catheter to be threaded through an opening in the supporting device for application or removal of that device is believed undesirable. In general, while a variety of catheter retention devices have been disclosed in the art, and while some of them have advantageous features, all of them are believed to have one or more serious shortcomings involving construction, operation, and/or effectiveness in use.
An important aspect of this invention therefore lies in providing an improved catheter retention device that is simple in construction and reliable in operation, may be securely attached to a patient without sutures, without threading the catheter through the device, and without obstructing visual inspection of the site after the device is in place, and is easily manipulated to clamp and immobilize a catheter and, if necessary, permit selective repositioning of the catheter in relation to the device. Furthermore, the device supports the catheter so that it extends at right angles to the skin at the entry point, protects the skin over a wide surrounding area, and at the same time exposes the immediate area of the incision or wound for direct visual inspection. The device may be easily manipulated by one hand, leaving the physician's other hand free for positioning the catheter or for performing other operations. Because of the security of the attachment between the device and the catheter, sutures connecting the two are unnecessary, but the retention device is designed to permit the use of such sutures in those exceptional circumstances where supplementary suturing is desired.
In brief, the device takes the form of an apertured, flexible, and resilient adhesive barrier pad upon which a molded plastic catheter support structure is mounted. An entry slit leads from the periphery of the pad to its central aperture or opening. The support structure includes an arcuate base affixed to the pad, a pair of spaced flexible support arms formed integrally with the base and projecting upwardly at opposite sides of the opening, and a pair of elongated clamping bars joined at intermediate points along their lengths to the upper ends of the flexible support arms. In a preferred embodiment, the bars are permanently joined together at one of their ends, have ratchet coupling means at their opposite ends, and have their axes askew so that the ratchet elements are disaligned and uncoupled when the device is supplied to a user. However, since the latching bars extend along parallel planes and are disposed in contiguous relation in an untensioned state, they are already in a relationship that approximates their closed condition and, when finally shifted into closed positions during use, have no internal forces or stresses urging them to spring apart into unlatched condition and exert no shear stresses at the interface between the support structure and pad.
Such a construction allows a user to position a catheter through the opening of the barrier pad by spreading the edges of the pad defining the entry slit, then simply urging the catheter laterally through that slit to the opening, and finally urging the edges of the slit together while at the same time adhesively securing the pad to the patient. The sealant barrier material of the pad joins together to close the slit and provide a continuous or uninterrupted annular barrier zone about the exit site, thereby protecting the surrounding skin from the excoriating effects caused by contact with exudate. In a preferred embodiment, the barrier material of the pad is covered with a layer of resilient foam to which the base of the support structure is secured. During the steps of closing the slit and adhesively securing the pad to a patient's skin, the edges of the resilient foam layer are also brought into contact with each other thereby enhancing the protection afforded by the pad. To facilitate closing of the slit during the steps of applying the pad, the base of the support structure is provided with a notch facing the inner end of the slit, the notch allowing the sections of the base on opposite sides of the slit to be urged together as the barrier pad is re-formed to close the slit and adhere the pad to the patient's skin.
Other features, objects, and advantages of the invention will become apparent from the specification and drawings.